How to Account for Alternatives When Comparing Effects: Revisiting 'Bringing Education to Afghan Girls'

TL;DR

This paper applies a principal strata approach to analyze how the effects of a girls' education intervention in Afghanistan vary over time, considering alternative schooling options and usage patterns, explaining differences in observed effects.

Contribution

It introduces a principal strata methodology to account for alternative options when comparing intervention effects across different years.

Findings

The share of girls benefiting from the intervention decreased in 2015.

The intervention was more effective for those who continued to benefit from it.

Effectiveness varied based on individuals' use of existing alternatives.

Abstract

This paper uses a "principal strata" approach to decompose treatment effects and interpret why a schooling intervention that yielded exceptional initial effects yielded substantially smaller effects in a replication years later. The specific application is a set of 2008 and 2015 replications of an intervention aiming to increase primary education for girls in rural Afghanistan. The intervention offers a new schooling option, and as such, its effects depend on how individuals use alternatives that already exist. The principal strata approach accounts variation in use patterns when comparing effects across the replications. Our findings show that even though the share of girls for whom the intervention would be valuable dropped considerably in 2015 as compared to 2008, the intervention was even more efficaciousness for those who continued to benefit from it.